The sicko UK muscle-car ballers at Marcos are working up a new version of the slithery TSO coupe, the GTC, which is set for an unveiling next week in London. The company says it's made 150 improvements, based on testing and customers' suggestions (e.g., faster! better! more! A little to the left!), including a lighter, stiffer body, custom exhausts and "bespoke engine management," which has something to do with software. It's still powered by a Chevy LS6 V8 and has the same Prodrive-built chassis as the TSO, and Marcos says the GTC will go from zero to 60 in 4.1 seconds. A targa-top version is planned for a later release.